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related to the presence of a combined valve prolapse and to an echocardiographic picture of valve diffuse thickening.110
2.5 PROGNOSTIC FACTORS IN ISCHEMIC STROKE
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30-day (36.2% vs. 16.8%, P < 0.0001) and at 1-year post-stroke (48.6% vs. 27.7%, P <
0.001), longer hospitalization, and greater disability at discharge (P < 0.001).115 LEVEL OF CONSCIOUSNESS
Level of consciousness on admission has a bearing on the outcome of stroke. the development of a decreased level of consciousness within the initial hours after stroke, is a powerful independent predictor of mortality after stroke.116Furthermore, the individual components of the Glasgow coma scale have been found to independently provide prognostic information (verbal and eye scores independently provide prognostic information .117
NEUROLOGIC SEVERITY
The severity of stroke on neurologic exam is probably the most important factor affecting short- and long-term outcome. As a general rule, large strokes with severe initial clinical deficits have poor outcomes compared with smaller strokes. Studies by Adams and his coworkers concluded that the NIHSS score strongly predicted the likelihood of a patient's recovery after stroke. A score of > or =16 forecasted a high probability of death or severe disability whereas a score of < or =6 forecasted a good recovery.118
Another report analyzed NIHSS scores obtained within 24 hours of acute ischemic stroke symptom onset from over 1200 patients enrolled in a clinical trial. Each additional point on the NIHSS decreased the odds of an excellent outcome at three months by 17 percent.119
On the other hand, this relationship was not established in intracerebral hemorrhage.
Dawodu and her co-worker observed that high NIHSS scores were not synonymous with mortality in first ever intracerebral haemorrhages. Decline in National institute of health
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stroke scale was to demise of patients, not improvement. Young adults had lower NIHSS scores but no appreciable outcome. Therefore, National institute of health stroke scale did show a different predictive pattern in haemorrhagic strokes.120
INFARCT VOLUME
The volume of acute infarction on neuroimaging studies may be used to estimate stroke outcome. In one small study, the volume of ischemic tissue determined by diffusion-weighted MRI within 36 hours of stroke onset combined with the NIHSS score and time from stroke onset to imaging predicted the functional outcome at three months better than any of the individual factors alone.121
A much larger study analyzed data from over 1800 patients who had CT or MRI within 72 hours of ischemic stroke onset and found that initial infarct volume was an independent predictor of stroke outcome at 90 days, along with age and NIHSS score.122
INFARCT LOCATION
The prognosis for stroke recovery may vary by the affected vascular territory and site of ischemic brain injury. Strokes in the insular region (supplied by the insular branch of the middle cerebral artery) have been associated with increased mortality, which is often attributed to autonomic dysregulation. 123
COMORBIDITIES
A host of pre-stroke comorbid conditions are associated with an increased risk of poor outcome following ischemic stroke, including the following:
ATRIAL FIBRILLATION.
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Stroke patients with AF were at high risk of death both at the acute phase of stroke and during the subsequent year after the first acute stroke event. Mortality from cardiac diseases prevailed in the AF group during the acute phase of stroke. 124
CANCER:
The presence of cancer adversely affects the long term and short term outcome of acute stroke.124
DIABETES MELLITUS:
The results of a study confirmed that admission glucose level (AGL) and history of diabetes mellitus were associated with poor clinical outcome after thrombolysis. It suggested that AGL may be a surrogate marker of brain infarction severity rather than a causal factor.125
MYOCARDIAL INFARCTION:
Mortality after Acute Myocardial Infarction complicated by an ischemic stroke was very high.
One study identified myocardial ischemia as a predictor of 30-day and 1-year mortality in stroke patients. 126
LOW HEMOGLOBIN LEVEL
Tanne et al observed that WHO-defined anemia was common in both men and women among patients with first ever acute stroke and predicted poor outcome. Moreover, the association between admission hemoglobin and mortality was not linear; risk for death increased at both extremes of hemoglobin. 127
2.6.0 PROGNOSIS OF INTRACEREBRAL HEMORRHAGE
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Approximately half of all ICH-related mortality occurs within the first 24 hours after the initial hemorrhage.128Mortality approaches 50% at 30 days.129 associated with poor outcomes include large hematoma volume (>30 mL), posterior fossa location, older age, mean arterial blood pressure (MAP) >130 mmHg at admission 130
A score of below 4 on the Glasgow Coma Scale (GCS) on admission. The same factors are also the most powerful predictors of mortality at 30 days. Hematoma expansion has also been shown to be an independent predictor of diminished functional outcomes, neurological deterioration and mortality,131 In a study by Alvarez-Sabín et al. increased levels of matrix metalloproteinase (MMP)-9 and MMP-3 at 24 hours were associated with increased peri-hematomal edema and mortality, respectively.132
2.6.1 COMPLICATIONS OF STROKE
In Nigeria, a recent study by Watila observed that the most common complications of stroke were aspiration pneumonia 65 (12.4%), depression 48 (9.2%), urinary tract infection 33 (6.3%), pressure sore 20 (3.8%), contractures 18 (3.4%), seizure 16 (3.1%) and hyperglycaemia 12 (2.3%). 133
In another study, complications during hospital admission were recorded in 265 (85%) of stroke patients. Specific complications were as follows: neurological-recurrent stroke (9%
of patients), epileptic seizure (3%); infections-urinary tract infection (24%), chest infection (22%), others (19%); mobility related-falls (25%), falls with serious injury (5%), pressure sores (21%); thromboembolism-deep venous thrombosis (2%), pulmonary embolism (1%);
pain-shoulder pain (9%), other pain (34%); and psychological-depression (16%), anxiety (14%), emotionalism (12%), and confusion (56%). 134
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